Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.13.1 (exoribonuclease)
 732 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The yeast nuclear gene DSS1 codes for a mitochondrial protein containing regions of homology to bacterial RNase II and can act as a multicopy suppressor of a deletion of the SUV3 gene, which encodes an RNA helicase. In order to establish the function of the DSS1 gene in mitochondrial biogenesis we studied RNA metabolism in yeast strains disrupted for SUV3 or DSS1. The results indicate that in the absence of DSS1 the in vitro activity of 3'-5' exoribonuclease is abolished and mitochondrial translation is blocked. In disruption strains harboring intronless mitochondrial genomes steady-state levels of COB mRNA and 16S rRNA were very low, while in the presence of a mitochondrial genome containing the omega intron in the 21S rRNA gene the excised intron accumulates. Moreover we observed an accumulation of precursors of 21S rRNA and the VAR1 mRNA. All these phenotypes are virtually identical to those of strains in which SUV3 is disrupted. We suggest that the DSS1 gene product, like the SUV3 gene product, is a subunit of the yeast mitochondrial degradosome (mtEXO), and that this protein complex participates in intron-independent turnover and processing of mitochondrial transcripts. In addition our studies exclude any role for the NUC1 nuclease in these phenomena.
 ...
PMID:The yeast nuclear gene DSS1, which codes for a putative RNase II, is necessary for the function of the mitochondrial degradosome in processing and turnover of RNA. 982 34

The cytochrome b gene in Saccharomyces cerevisiae, COB, is encoded by the mitochondrial genome. Nuclear-encoded Cbp1 protein is required specifically for COB mRNA stabilization. Cbp1 interacts with a CCG element in a 64-nucleotide sequence in the 5'-untranslated region of COB mRNA. Mutation of any nucleotide in the CCG causes the same phenotype as cbp1 mutations, i.e., destabilization of both COB precursor and mature message. In this study, eleven nuclear suppressors of single-nucleotide mutations in CCG were isolated and characterized. One dominant suppressor is in CBP1, while the other 10 semidominant suppressors define five distinct linkage groups. One group of four mutations is in PET127, which is required for 5' end processing of several mitochondrial mRNAs. Another mutation is linked to DSS1, which is a subunit of mitochondrial 3' --> 5' exoribonuclease. A mutation linked to the SOC1 gene, previously defined by recessive mutations that suppress cbp1 ts alleles and stabilize many mitochondrial mRNAs, was also isolated. We hypothesize that the products of the two uncharacterized genes also affect mitochondrial RNA turnover.
 ...
PMID:Suppressor analysis of mutations in the 5'-untranslated region of COB mRNA identifies components of general pathways for mitochondrial mRNA processing and decay in Saccharomyces cerevisiae. 1010 Nov 59